Parallel Interleaved Three-level Inverters Operation with Continuous and Discontinuous PWM Methods

Abstract

The interleaved operation based on applying carrier based pulse-width modulation (CB-PWM) methods is a efficient way to improve the performance of power systems formed by the parallel connection of several power modules. This method leads to the elimination of some sidebands harmonics in the output waveforms improving differential and common-mode performances at the expense of increasing the circulating currents. In this paper, interleaved continuous and discontinuous CB-PWM methods are evaluated in order to find the most suitable modulation method for two parallel-connected three-level inverters considering the load current THD minimization as the main objective, but also analyzing other converter features such as common-mode voltage and circulating currents.